The invention relates to a method for step-by-step conveying according to the introductory part of Claim 1, an apparatus for step-by-step conveying according to the introductory part of Claim 8, and a turning module according to the introductory part of Claim 11.
An apparatus for step-by-step conveying of containers is known from WO99/39849. It has bars arranged alongside the containers and provided with pushers which, by a converging movement of the bars, take hold of the containers (which are standing in line, spaced apart, on a conveyor plate), advance the containers one step in the conveying direction by a forwards movement of the bars, let go of the containers by a diverging movement of the bars, and then by a one step backwards movement of the bars revert to the pick-up position, where the process repeats itself. As the container bodies in this example are being conveyed in a machine line of modular construction to processing modules which intervene in the bodies from above, the bodies, after being conveyed a certain distance, are turned over so that their other end (which is the bottom end, if the containers have been fed into the sequence of processing stations top end up first) can be processed in processing modules downstream of the turning module. The turning module has a beam pivotable about an axis transverse with respect to the conveying direction, on which beam the container is held magnetically. The beam turns the container over in the conveying direction and places the overturned container on a conveyor plate, where it is seized by the bars of the next step-by-step conveyor. This conventional way of turning the container bodies takes up a lot of room in the conveying direction, particularly for tall containers.
Therefore the basic problem which the invention seeks to solve is to provide a method and an apparatus, and also a turning module, which do not have these disadvantages.
In the case of the method stated at the outset thisproblem is solved by the characterizing features of Claim 1, and in the case of the apparatus of the kind stated at the outset, by the characterizing features of Claim 8. In the case of a turning module of the kind stated at the outset the problem is solved by the characterizing features of Claim 11.
Rotating transversely across the conveyor path, and especially rotating xe2x80x9con the spotxe2x80x9d without displacement in the conveying direction, means that the length needed in the conveying direction for the turning operation becomes independent of the height of the article.
It is especially preferred that conveying should cease to be in spaced-apart mode in the turning zone, and give way to a conveying mode in which the article entering the turning zone pushes the overturned article out of the turning zone. The article can then be picked up again by a step-by-step conveyor and conveyed to the subsequent processing stations. Through this preferred transition from spaced-apart conveying to direct-contact conveying in the turning zone, much space can be saved in the design of the turning zone.